EP0060787A1 - Process for the preparation of ethylene glycol - Google Patents

Process for the preparation of ethylene glycol Download PDF

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Publication number
EP0060787A1
EP0060787A1 EP82400452A EP82400452A EP0060787A1 EP 0060787 A1 EP0060787 A1 EP 0060787A1 EP 82400452 A EP82400452 A EP 82400452A EP 82400452 A EP82400452 A EP 82400452A EP 0060787 A1 EP0060787 A1 EP 0060787A1
Authority
EP
European Patent Office
Prior art keywords
hydrogen
oxalate
copper
catalyst
psia
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP82400452A
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German (de)
English (en)
French (fr)
Inventor
Fedor Poppelsdorf
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Union Carbide Corp
Original Assignee
Union Carbide Corp
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Filing date
Publication date
Application filed by Union Carbide Corp filed Critical Union Carbide Corp
Publication of EP0060787A1 publication Critical patent/EP0060787A1/en
Ceased legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/132—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
    • C07C29/136—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH
    • C07C29/147—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of carboxylic acids or derivatives thereof
    • C07C29/149—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of carboxylic acids or derivatives thereof with hydrogen or hydrogen-containing gases
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Definitions

  • This invention relates to the preparation of ethylene glycol by the vapor phase hydrogenation of oxalate esters.
  • U.S. Patent No. 2,060,880 discloses a process for the hydrogenation of di-alkyl esters of oxalic acid at a pressure in excess of 200 atmospheres over a copper chromite catalyst to produce ethylene glycol.
  • Other esters of oxalic acid may also be employed.
  • U.S. Pat. No. 2,305,104 discloses a process for the vapor phase hydrogenation of alkyl esters of hydroxy acetic acid utilizing a dual_catalyst charged reaction zone at temperatures between 150°C., and 300°C., and pressures from 10 to 1000 atmospheres or higher.
  • British Pat. Nos. 555,240 and 575,380 disclose processes for the vapor phase catalytic hydrogenation of hydroxy acetic acid and its derivatives (esters) and an ester of glycollic acid respectively at temperatures ranging from 150°C. to 300°C., and pressures of from 10 to 1000 atmospheres to produce ethylene glycol.
  • U.S. Pat. No. 4,112,245 discloses a process for the preparation of ethylene glycol by hydrogenation of oxalate esters in the vapor phase wherein the process is characterized by having a sulfur content in said oxalate ester less than 0.4 ppm and having an essentially sulfur free hydrogen in the presence of a copper-containing hydrogenation catalyst.
  • 1,2-butanediol content tracks water content and is a predominant impurity when the water content is about 1 weight percent.
  • Typical of other reaction by-products which can be formed during hydrogenation of dialkyl oxalates are: water; methanol; ethanol; ethylene glycol monoacetate; Cellosolve (TM); 1,2-butanediol; 2-hydroxymethyl-1,3-dioxolane; 2-methyl-1,3-dioxolane; 2-methyl-4-ethyl-1,3-dioxolane; ethyl glycolate; and diethylene glycol.
  • TM Cellosolve
  • 1,2-butanediol 2-hydroxymethyl-1,3-dioxolane
  • 2-methyl-1,3-dioxolane 2-methyl-4-ethyl-1,3-dioxolane
  • ethyl glycolate ethyl glycolate
  • diethylene glycol diethylene glycol
  • the ethylene glycol used in its manufacture must have a certain constant level of purity to insure that the chemical and physical properties of the polyester fiber are relatively constant.
  • impurities are extremely difficult to remove, yet ethylene glycol containing even minute quantities of such impurities, such as up to 1.0 percent by weight, is rendered commercially unusable.
  • the impurity is 1,2-butanediol
  • the use of standard separation techniques is difficult. For example, if distillation is employed for separation, the separation is difficult owing to the fact that the boiling point of 1,2-butanediol at atmospheric pressure is about 192°C., .
  • ethylene glycol has a boiling point of about 198°C.
  • this asymmetrical diol is a hiqhly undesirable component in ethylene glycol owing to the effect it has the characteristics of polyester fiber made from ethylene glycol containing it.
  • 1,2-butanediol is not more than about 1.0 percent by weight, viz. 0.1 to 1.0 weight percent, the resulting ethylene glycol will be, for all practical purposes, unusable for use in the manufacture of polyester fiber, owing to the necessity of employing special purification processes, and thus will result in the use of such ethylene glycol for applications requiring lesser purity. This will necessarily decrease the commercial value of such ethylene glycol.
  • the instant process is for preparing of ethylene glycol containing not more than 1.0 percent by weight 1,2-butanediol which comprises reacting a stream of a vaporous mixture of hydrogen and an alkyl oxalate having the formula: wherein R is methyl or ethyl.
  • the molar ratio of hydrogen to dialkyl oxalate in the reaction is greater than 4:1 and is at a pressure of between about 15 psia and about 1000 psia.
  • the temperature is between about 180°C.
  • the process is carried out over an effective amount of a solid copper-containing hydrogenation catalyst.
  • the process of this invention correlates the process conditions, i.e., temperature, pressure, SV and LHSV and molar ratio of hydrogen to dialkyl oxalate, such that not more than 1.0 percent by weight 1,2-butanediol is formed.
  • the invention relates to the preparation of ethylene glycol essentially free of deleterious amounts of 1,2-butanediol by the hydrogenation of methyl or ethyl oxalate in the vapor phase at elevated temperature in the presence of a copper-containing hydrogenation catalyst.
  • the oxalate esters which may be employed in the process of the invention have the general formula: wherein R is methyl or ethyl.
  • the oxalate esters are preheated and vaporized, as may be determined by their vapor pressure, to insure that essentially all of the ester is in the vapor state when passed, along with hydrogen, over the catalyst bed.
  • the catalyst bed is maintained at a temperature high enough to prevent condensation of the oxalate ester or the product ethylene glycol.
  • the molar ratio of hydrogen to alkyl oxalate is greater than 4:1.
  • the preferred molar ratio is between about 20:1 and about 135:1 and most preferably between about 30:1 and about 70:1.
  • Higher or lower ratios of hydrogen to oxalate ester may be employed in the process provided the alkyl oxalate is in the vapor state and hydrogen is employed in the process in at least the stoichiometric ratio of hydrogen to alkyl oxalate of 4:1.
  • a molar amount of inert gas i.e., inert in the hydrogenation process, such as methane or nitrogen
  • inert gas such as methane or nitrogen
  • the combined molar ratio of hydrogen and inert gas (e.g. methane or nitrogen) to the oxalate ester is between about 20:1 and about 135:1 and preferably between about 30:1 and about 70:1, although other molar ratios may be employed so long as the hydrogen to oxalate ratio is greater than 4:1.
  • the hydrogenation catalysts employed in the process of the invention have been generally described in the prior art and any known solid copper-containing hydrogenation catalyst, or mixture of solid copper-containing catalysts, useful for the conversion of esters to alcohols may be employed.
  • hydrogenation catalysts containing copper either in the elemental form or combined with oxygen, as well as other hydrogenating metal oxides employed in conjunction with copper, supported or unsupported may be used.
  • Preferred catalysts are the copper zinc chromite or copper chromite catalysts which may be promoted with barium or sodium hydroxide and which have been reduced or partially reduced with hydrogen.
  • Representative hydrogenation catalysts suitable for use in this invention include, for example, in addition to those above noted, zinc, copper, cadmium, chromite catalyst, copper ammonium chromate and zinc chromium oxide so long as at least some amount of a solid copper-containing catalyst is present.
  • Other catalysts which may be suitable for use in the process comprise compositions of tin, silver, cadmium, ruthenium, zinc or lead and oxides of these metals containing chromium in admixture with solid copper-containing catalysts.
  • copper-containing hydrogenation catalysts are commercially available such as copper zinc chromite catalyst, copper barium chromite catalyst, sodium hydroxide-promoted copper chromite and copper chromite catalysts such as Calsicat's (TM) Code E-103TR (Calsicat (TM) is a division of Mallinckrodt, Inc.).
  • the relative activity of a given solid copper-containing hydrogenation catalyst may be determined by the rate (in gram moles liter haur -1 ) at which it produces the product ethylene glycol over a fixed period of time.
  • a lower activity for a given catalyst is indicated by a lower rate relative to the rate of the catalyst as measured prior to any loss of activity from use in the process.
  • a copper chromite hydrogenation catalyst Calsicat (TM) Code No. E-103TR
  • the catalyst is purchased as a a pellet and then crushed such that the catalyst employed for hydrogenation has an irregular shape and a particle size between about 8 to about 14 mesh (U. S. Standard).
  • This catalyst is partially reduced and stabilized, i.e., has at least a portion of the copper in the zero oxidation state, and has the following typical properties:
  • the catalyst was diluted with a solid inert diluent of approximately an equal amount by volume.
  • the solid inert diluent was an alpha-alumina which has a relatively low surface area, a shape and size similar to that of the copper chromite catalyst and possessed the following typical properties:
  • the instant process is advantageous in that by correlating the process conditions, the formation of 1,2-butanediol is minimized such that the concentration is less than 1.0 percent by weight, preferably less than about 0.5 percent by weight, and most preferably less than about 0.1 percent - by weight, based on the weight of ethylene glycol.
  • the amount of 1,2-butanediol formed in the process can be related to the amount of water formed in the process.
  • the temperature of the hydrogenation catalyst is generally maintained between about 180°C. and about 240°C., preferably between 190°C. and about 210°C., and most preferably between about 200°C. and about 210°C.
  • the selection of temperature is such that it is chosen between about 180°C. and about 240°C. so that the formation of 1,2-butanediol in the process can be less than 1.0 percent by weight of products by correlating the temperature, pressure, space velocity and liquid hourly space velocity.
  • the pressure employed in the process is not narrowly critical and is generally between about 15 psia and about 1000 psia, preferably between about 100 psia and about 1000 psia and most preferably between about 500 psia and about 1000 psia.
  • SV and LHSV are defined herein as: where:
  • the process is carried out with a space velocity of between about 3000 hr -1 and about 25,000 hr -1 and preferably between about 8,000 hr -1 and about 18,000 hr -1 .
  • the liquid hourly space velocity is generally between about 0.001 hr -1 and about 5.0 hr -1 and preferably between about 1.0 hr -1 and about 3.0 hr -1 .
  • the hydrogen used in the process is similarly purified by a conventional gas scrubbing technique such that less than about 0.4 ppm each of sulfur and.chlorine and sulfur and chlorine containing compounds are present.
  • Typical of such conventional methods is the passing of the hydrogen through a bed of a mixture of Fe 2 0 3 and fly ash, or through a bed of CuO/ZnO.
  • the process may be carried out in any suitable reactor such as a continuous-flow tubular reactor, wherein the oxalate ester is heated to the vapor state and admixed with hydrogen at the desired temperatures and pressures in the presence of a copper-containing hydrogenation catalyst which may be in the form of a fixed or dynamic (e.g., fluidized) catalyst bed.
  • a copper-containing hydrogenation catalyst which may be in the form of a fixed or dynamic (e.g., fluidized) catalyst bed.
  • the vapor phase hydrogenation reaction is exothermic in nature and the tubular reactor, if employed, is preferably cooled by external cooling means to maintain the reaction temperature in the desired range.
  • the vaporous reaction products may be recovered and treated by any conventional process, e.g., distillation, and since the process is preferably carried out in a continuous manner said recovery process will preferably include recycling of hydrogen and like reusable components, such as the oxalate reactant.
  • the condensate collected in the coil-type condenser is degassed by gravity feeding it to a high-pressure separator followed by a low-pressure separator. Liquid and gaseous samples are then taken for analysis.
  • the liquid reaction products were analyzed by gas chromatography using a 10 foot x 1/8 inch stainless steel column packed with TENAX (TM) GC 60/80 mesh, using helium as the carrier gas (15 ml/min) with an injector temperature of about 90°C. to about 320°C. with the temperature increasing at about 8°C. per minute.
  • TM TENAX
  • a thermal conductivity detector maintained at 300°C. was used for detection. The following are typical retention times observed for the following compounds:
  • the gaseous reaction products were analyzed on a continuous basis by a Vapor Fraction Analyzer (VFA) supplied by solenoid driven demi-valves and three separate analyzers and detectors. Two analyzers were equipped with thermal conductivity detectors and the third analyzer was equipped with a photometric flame-ionization detector. In each case, the quantitation was by peak height measurement.
  • the carrier gas was hydrogen (50 psia) for the analyzer used for hydrogen detection.
  • Examples 1-3 were carried out by charging 103 cubic centimeters of a copper chromite catalyst comprising 53 cubic centimeters of Calsicat (TM) cooper chromite (Code E-103TR), prepared as above described, and 50 cubic centimeters of the solid inert diluent above described, in a tube reactor, as above described.
  • Dimethyl oxalate and hydrogen, containing less than about 0.4 ppm sulfur and chlorine, were preheated at about 200°C., thereby vaporizing the dimethyl oxalate.
  • the vaporized oxalate/hydrogen mixture was introduced into the reactor and over the solid copper-containing catalyst. Table I sets forth reaction conditions and some results for Examples 1 to 3.
  • Standard conditions is meant to refer to the following conditions for hydrogenation:

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
EP82400452A 1981-03-12 1982-03-12 Process for the preparation of ethylene glycol Ceased EP0060787A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US23976481A 1981-03-12 1981-03-12
US239764 1981-03-12

Publications (1)

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EP0060787A1 true EP0060787A1 (en) 1982-09-22

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EP82400452A Ceased EP0060787A1 (en) 1981-03-12 1982-03-12 Process for the preparation of ethylene glycol

Country Status (6)

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EP (1) EP0060787A1 (enrdf_load_stackoverflow)
JP (1) JPS57167936A (enrdf_load_stackoverflow)
AU (1) AU547796B2 (enrdf_load_stackoverflow)
BR (1) BR8201302A (enrdf_load_stackoverflow)
ES (1) ES510330A0 (enrdf_load_stackoverflow)
ZA (1) ZA821646B (enrdf_load_stackoverflow)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0097262A3 (en) * 1982-05-28 1984-02-15 Ube Industries, Ltd. A hydrogenation catalyst composition for the hydrogenation of an oxalate diester, a process for preparing same and the use thereof
EP0169396A1 (de) * 1984-06-26 1986-01-29 BASF Aktiengesellschaft Verfahren zur Herstellung von 1,4-Butandiol
US4584419A (en) * 1983-11-29 1986-04-22 Davy Mckee Ltd. Process for the production of butane-1,4-diol
US4649226A (en) * 1986-03-27 1987-03-10 Union Carbide Corporation Hydrogenation of alkyl oxalates
US4652685A (en) * 1985-11-15 1987-03-24 General Electric Company Hydrogenation of lactones to glycols
US5004845A (en) * 1981-08-20 1991-04-02 Davy Mckee (London) Limited Hydrogenation of aldehydes
US5030609A (en) * 1987-07-29 1991-07-09 Davy Mckee (London) Limited Process for producing a hydrogenation catalyst of copper chromite
CN101475441B (zh) * 2008-12-18 2012-05-09 中国石油化工股份有限公司 草酸酯生产乙二醇的方法
US10086364B2 (en) * 2014-06-26 2018-10-02 University Of Wyoming Methods of catalytic hydrogenation for ethylene glycol formation
CN109569619A (zh) * 2017-09-29 2019-04-05 中国石油化工股份有限公司 催化剂组合物、制造方法及用途
CN109569620A (zh) * 2017-09-29 2019-04-05 中国石油化工股份有限公司 催化剂组合物、合成方法及用途
WO2020061745A1 (zh) * 2018-09-25 2020-04-02 高化学技术株式会社 铜基催化剂及其制备方法和使用该催化剂制备乙二醇的方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1149695B (it) * 1982-02-26 1986-12-03 Pirelli Cinghia dentata

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4112245A (en) * 1976-08-18 1978-09-05 Atlantic Richfield Company Process for the preparation of ethylene glycol
DE2936700A1 (de) * 1978-09-14 1980-03-27 Montedison Spa Verfahren zur selektiven katalytischen hydrierung von oxalsaeurediestern

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4112245A (en) * 1976-08-18 1978-09-05 Atlantic Richfield Company Process for the preparation of ethylene glycol
DE2936700A1 (de) * 1978-09-14 1980-03-27 Montedison Spa Verfahren zur selektiven katalytischen hydrierung von oxalsaeurediestern
GB2031883A (en) * 1978-09-14 1980-04-30 Montedison Spa Catalytic hydrogenation of oxalic esters

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5004845A (en) * 1981-08-20 1991-04-02 Davy Mckee (London) Limited Hydrogenation of aldehydes
EP0097262A3 (en) * 1982-05-28 1984-02-15 Ube Industries, Ltd. A hydrogenation catalyst composition for the hydrogenation of an oxalate diester, a process for preparing same and the use thereof
US4584419A (en) * 1983-11-29 1986-04-22 Davy Mckee Ltd. Process for the production of butane-1,4-diol
EP0169396A1 (de) * 1984-06-26 1986-01-29 BASF Aktiengesellschaft Verfahren zur Herstellung von 1,4-Butandiol
US4652685A (en) * 1985-11-15 1987-03-24 General Electric Company Hydrogenation of lactones to glycols
US4649226A (en) * 1986-03-27 1987-03-10 Union Carbide Corporation Hydrogenation of alkyl oxalates
US5030609A (en) * 1987-07-29 1991-07-09 Davy Mckee (London) Limited Process for producing a hydrogenation catalyst of copper chromite
CN101475441B (zh) * 2008-12-18 2012-05-09 中国石油化工股份有限公司 草酸酯生产乙二醇的方法
US10086364B2 (en) * 2014-06-26 2018-10-02 University Of Wyoming Methods of catalytic hydrogenation for ethylene glycol formation
CN109569619A (zh) * 2017-09-29 2019-04-05 中国石油化工股份有限公司 催化剂组合物、制造方法及用途
CN109569620A (zh) * 2017-09-29 2019-04-05 中国石油化工股份有限公司 催化剂组合物、合成方法及用途
CN109569619B (zh) * 2017-09-29 2021-11-30 中国石油化工股份有限公司 催化剂组合物、制造方法及用途
CN109569620B (zh) * 2017-09-29 2021-11-30 中国石油化工股份有限公司 催化剂组合物、合成方法及用途
WO2020061745A1 (zh) * 2018-09-25 2020-04-02 高化学技术株式会社 铜基催化剂及其制备方法和使用该催化剂制备乙二醇的方法

Also Published As

Publication number Publication date
JPS57167936A (en) 1982-10-16
ES8302616A1 (es) 1983-02-01
AU8133282A (en) 1982-09-16
JPS6247857B2 (enrdf_load_stackoverflow) 1987-10-09
ES510330A0 (es) 1983-02-01
ZA821646B (en) 1983-01-26
BR8201302A (pt) 1983-01-25
AU547796B2 (en) 1985-11-07

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